1. Field of the Invention
This invention relates to brakes and, in particular, to a cam actuated drum brake that enables the use of brake linings having increased thickness as compared to conventional brakes.
2. Discussion of Related Art
A conventional drum brake includes a brake drum that rotates with a wheel or wheels proximate one end of an axle. The brake drum defines a radially inner braking surface. A brake spider is disposed about the axle and supports an anchor pin that extends axially from the spider. A pair of brake shoes are pivotally mounted on the anchor at a first end. Each brake shoes includes a roller, or cam follower, proximate a second end. A generally S-shaped cam engages the rollers in the brake shoes and rotation of the cam moves the brake shoes between positions of engagement and disengagement with the braking surface of the brake drum.
The brake shoes in a conventional drum brake include brake linings that create a frictional engagement with the braking surface of the brake drum upon actuation of the brake. The brake linings are subject to wear and deterioration. As a result, the linings must be replaced periodically. Replacement of the linings is a significant cost to vehicle fleet operators because of the costs associated with the actual repair and maintenance of the brake and the loss of vehicle operating time.
The inventors herein have recognized a need for a brake and associated brake components that will minimize and/or eliminate one or more of the above-identified deficiencies.